Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

Ruins of Oran-Rief

Ruins of Oran-Rief enters tapped.
{T}: Add {C}. ({C} represents colorless mana.)
{T}: Put a +1/+1 counter on target colorless creature that entered this turn.

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have Phyrexian Metamorph enter as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Sword of the Meek

Equipped creature gets +1/+2.
Equip {2}
Whenever a 1/1 creature enters under your control, you may return Sword of the Meek from your graveyard to the battlefield, then attach it to that creature.

Izzet Signet

Vault of Whispers

Roterothopter

Flying
{2}: Roterothopter gets +1/+0 until end of turn. Activate no more than twice each turn.

Ghirapur Gearcrafter

When Ghirapur Gearcrafter enters, create a 1/1 colorless Thopter artifact creature token with flying. (A creature with flying can't be blocked except by creatures with flying or reach.)

Cranial Plating

Equipped creature gets +1/+0 for each artifact you control.
{B}{B}: Attach Cranial Plating to target creature you control.
Equip {1}

Stoic Rebuttal

Metalcraft — This spell costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Pilgrim's Eye

Flying
When Pilgrim's Eye enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Arcane Sanctum

Arcane Sanctum enters tapped.
{T}: Add {W}, {U}, or {B}.

Sea Gate Wreckage

{T}: Add {C}. ({C} represents colorless mana.)
{2}{C}, {T}: Draw a card. Activate only if you have no cards in hand.

Master Trinketeer

Servos and Thopters you control get +1/+1.
{3}{W}: Create a 1/1 colorless Servo artifact creature token.

Boros Signet

Thopter Assembly

Flying
At the beginning of your upkeep, if you control no Thopters other than Thopter Assembly, return Thopter Assembly to its owner's hand and create five 1/1 colorless Thopter artifact creature tokens with flying.

Sculpting Steel

You may have Sculpting Steel enter as a copy of any artifact on the battlefield.

Pia Nalaar

When Pia Nalaar enters, create a 1/1 colorless Thopter artifact creature token with flying.
{1}{R}: Target artifact creature gets +1/+0 until end of turn.
{1}, Sacrifice an artifact: Target creature can't block this turn.

Swamp

Snare Thopter

Ancient Den

Whirlermaker

{4}, {T}: Create a 1/1 colorless Thopter artifact creature token with flying.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Dragonskull Summit

Dragonskull Summit enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Herald of Kozilek

Devoid (This card has no color.)
Colorless spells you cast cost {1} less to cast.

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Paradoxical Outcome

Return any number of target nonland, nontoken permanents you control to their owners' hands. Draw a card for each card returned to your hand this way.

Rakdos Signet

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Dimir Signet

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. Caves of Koilos deals 1 damage to you.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Breya, Etherium Shaper

When Breya, Etherium Shaper enters, create two 1/1 blue Thopter artifact creature tokens with flying.
{2}, Sacrifice two artifacts: Choose one —
• Breya deals 3 damage to target player or planeswalker.
• Target creature gets -4/-4 until end of turn.
• You gain 5 life.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Decoction Module

Whenever a creature you control enters, you get {E} (an energy counter).
{4}, {T}: Return target creature you control to its owner's hand.

Etherium Sculptor

Artifact spells you cast cost {1} less to cast.

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

Counterspell

Thopter Spy Network

At the beginning of your upkeep, if you control an artifact, create a 1/1 colorless Thopter artifact creature token with flying.
Whenever one or more artifact creatures you control deal combat damage to a player, draw a card.

Aspiring Aeronaut

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Aspiring Aeronaut enters, create a 1/1 colorless Thopter artifact creature token with flying.

Telethopter

Tap an untapped creature you control: Telethopter gains flying until end of turn.

Copy Artifact

You may have Copy Artifact enter as a copy of any artifact on the battlefield, except it's an enchantment in addition to its other types.

Sol Ring

Mountain

Sharding Sphinx

Flying
Whenever an artifact creature you control deals combat damage to a player, you may create a 1/1 blue Thopter artifact creature token with flying.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Experimental Aviator

Flying
When Experimental Aviator enters, create two 1/1 colorless Thopter artifact creature tokens with flying.

Plains

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Ashnod's Altar

Goblin Welder

{T}: Choose target artifact a player controls and target artifact card in that player's graveyard. If both targets are still legal as this ability resolves, that player simultaneously sacrifices the artifact and returns the artifact card to the battlefield.

Flowstone Thopter

{1}: Flowstone Thopter gets +1/-1 and gains flying until end of turn.

Drill-Skimmer

Flying
Drill-Skimmer has shroud as long as you control another artifact creature. (It can't be the target of spells or abilities.)

Azorius Signet

Animation Module

Whenever one or more +1/+1 counters are put on a permanent you control, you may pay {1}. If you do, create a 1/1 colorless Servo artifact creature token.
{3}, {T}: Choose a counter on target permanent or player. Give that permanent or player another counter of that kind.

Nim Deathmantle

Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay {4}. If you do, return that card to the battlefield and attach Nim Deathmantle to it.
Equip {4}

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Thopter Engineer

When Thopter Engineer enters, create a 1/1 colorless Thopter artifact creature token with flying.
Artifact creatures you control have haste. (They can attack and {T} as soon as they come under your control.)

Pia and Kiran Nalaar

When Pia and Kiran Nalaar enters, create two 1/1 colorless Thopter artifact creature tokens with flying.
{2}{R}, Sacrifice an artifact: Pia and Kiran Nalaar deals 2 damage to any target.

Spined Thopter

({U/P} can be paid with either {U} or 2 life.)
Flying

Seat of the Synod

City of Brass

Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Daretti, Scrap Savant

+2: Discard up to two cards, then draw that many cards.
−2: Sacrifice an artifact. If you do, return target artifact card from your graveyard to the battlefield.
−10: You get an emblem with "Whenever an artifact is put into your graveyard from the battlefield, return that card to the battlefield at the beginning of the next end step."
Daretti, Scrap Savant can be your commander.

Darksteel Citadel

Whirler Rogue

When Whirler Rogue enters, create two 1/1 colorless Thopter artifact creature tokens with flying.
Tap two untapped artifacts you control: Target creature can't be blocked this turn.

Foundry of the Consuls

{T}: Add {C}.
{5}, {T}, Sacrifice Foundry of the Consuls: Create two 1/1 colorless Thopter artifact creature tokens with flying.

Hangarback Walker

Hangarback Walker enters with X +1/+1 counters on it.
When Hangarback Walker dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on Hangarback Walker.
{1}, {T}: Put a +1/+1 counter on Hangarback Walker.

Nomad Outpost

Nomad Outpost enters tapped.
{T}: Add {R}, {W}, or {B}.

Scourglass

{T}, Sacrifice Scourglass: Destroy all permanents except for artifacts and lands. Activate only during your upkeep.

Thopter Foundry

{1}, Sacrifice a nontoken artifact: Create a 1/1 blue Thopter artifact creature token with flying. You gain 1 life.

Thopter Squadron

Flying
Thopter Squadron enters with three +1/+1 counters on it.
{1}, Remove a +1/+1 counter from Thopter Squadron: Create a 1/1 colorless Thopter artifact creature token with flying. Activate only as a sorcery.
{1}, Sacrifice another Thopter: Put a +1/+1 counter on Thopter Squadron. Activate only as a sorcery.

Krark-Clan Ironworks

Whirler Virtuoso

When Whirler Virtuoso enters, you get {E}{E}{E} (three energy counters).
Pay {E}{E}{E}: Create a 1/1 colorless Thopter artifact creature token with flying.

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.

Scrap Mastery

Each player exiles all artifact cards from their graveyard, then sacrifices all artifacts they control, then puts all cards they exiled this way onto the battlefield.

Fabrication Module

Whenever you get one or more {E} (energy counters), put a +1/+1 counter on target creature you control.
{4}, {T}: You get {E}.

Mystic Monastery

Mystic Monastery enters tapped.
{T}: Add {U}, {R}, or {W}.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Foundry Inspector

Island

Foreboding Ruins

As Foreboding Ruins enters, you may reveal a Swamp or Mountain card from your hand. If you don't, Foreboding Ruins enters tapped.
{T}: Add {B} or {R}.

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Clever Impersonator

You may have Clever Impersonator enter as a copy of any nonland permanent on the battlefield.

Time Sieve

{T}, Sacrifice five artifacts: Take an extra turn after this one.

Eldrazi Displacer

Devoid (This card has no color.)
{2}{C}: Exile another target creature, then return it to the battlefield tapped under its owner's control. ({C} represents colorless mana.)

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters tapped unless you control two or more basic lands.

Port Town

As Port Town enters, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters tapped.
{T}: Add {W} or {U}.